Decolourization and Detoxification of Azo Dye, Malachite Green by Pseudomonas monteilii Strain RZT1, a Bacterium Isolated from Textile Wastewater

Discharge of textile industrial effluent without proper treatment has become a severe hazard for the animal health and environment worldwide. Therefore, this study was designed to isolate azo dye-degrading bacteria from textile wastewater and evaluate their ability to biodegrade reactive dyes into non-toxic products. The potent bacterial strain which was isolated from textile wastewater was identified as Pseudomonas monteilii strain RZT1 on the basis of 16S rDNA sequence. The isolated bacterial strain exhibited good decolorization ability with yeast extract supplementation as cosubstrate in static conditions for Malachite Green dye. The optimal condition for the decolorization of Malachite Green dye by P. monteilii strain RZT1 were at pH 7.0 and 28癈. Decolorization rates of Malachite Green dye by P. monteilii strain RZT1 were varied with initial dye concentration as follow: 84.8%, 75.4%, 63.4% and 45.5% decolorization for 100ppm, 200ppm, 300ppm and 400ppm initial dye concentration respectively. We investigated the effects of dyes used in the textile industry on the seed germination of Five crops - Rice (Oryza sativa), Wheat (Triticum aestivum L.), Khesari (Lathyrus sativus), Mustard (Brassica nigra) and Bitter Melon (Momordica charantia). It was found that textile dye Malachite Green had negative effect on seed germination and seedling growth in test cultures. The harmful effects of dye on seed germination and early seedling growth parameters were augmented with increase of dye concentration. Interestingly, treatment of the Malachite Green dye with isolated bacteria reduced the adverse effects of that dye on seed germination and seedling growth. Thus, it indicated the potentiality of P. monteilii strain RZT1 for bioremediation of textile effluents into a non-toxic form for plants.

Reduction of Toxic Effects of Textile Dye, Basic Red-18 on Tilapia Fish by Bioremediation with a Novel Bacterium, Mangrovibacter yixingensis Strain AKS2 Isolated from Textile Wastewater

Due to rapid industrialization and market demand of vibrant textile products, the natural textile dyes have been replaced by the synthetic textile dyes. These synthetic dyes are released in environment with textile wastewater resulting in a major environmental pollution, especially in aquatic ecosystem. Hence, aquatic organisms like fish are highly vulnerable to the pollution caused by dyes of textile wastewater. This study was designed to evaluate the deleterious effects of Basic Red-18 (BR-18) dye on behavior, survivability, haematology and histology of Tilapia fish (Tilapia mossambica) and to minimize these deleterious effects of BR-18 dye by bioremediation with the novel bacteria isolated from textile wastewater. The isolated novel bacteria was identified as Mangrovibacter yixingensis strain AKS2 by 16s rRNA sequencing (Accession no. OM189530). The 30% and 70% mortality rates were observed in fish exposed to commercial BR-18 dye at concentrations of 100 and 200 ppm respectively. Interestingly, the mortality rate of fish was decreased significantly to 10% and 20% when fish were exposed to 100 and 200 ppm BR-18 dye respectively after bioremediation with M. yixingensis strain AKS2. Fish exposed to tap water and bioremediated BR-18 dye solution exhibited typical behavioral responses, whereas fish exposed to commercial BR-18 dye solution exhibited anomalous behavior. Fish subjected to commercial BR-18 dye solution displayed decreased RBC, Hb, but increased WBC levels, demonstrating the dye's haemotoxicity. Contrary, no remarkable haematological toxic effect was found when fish were exposed to bioremediated BR-18 dye indicating the non-toxic character of the bioremediated dye metabolites. Similarly, extensive histological abnormalities in the gill, liver, intestinal, stomach, and heart tissues were seen when fish was cultured in commercial BR-18 dye, but the abnormalities were less significant when fish were raised in bioremediated BR-18 dye. Altogether, it can be concluded that BR-18 dye are toxic to fish, but this toxicity can be minimized by bioremediation with M. yixingensis strain AKS2.

Characterization of the biosorption of fast black azo dye K salt by the bacterium Rhodopseudomonas palustris 51ATA strain

BACKGROUND: Removal of dyes from wastewater by microorganisms through adsorption, degradation, or accumulation has been investigated. Biological methods used for dye treatment are generally always effective and environmentally friendly. In this study, biosorption of the Fast Black K salt azo dye by the bacterium Rhodopseudomonas palustris 51ATA was studied spectrophotometrically, at various pH (2­10), temperatures (25°C, 35°C, and 45°C) and dye concentrations (25­400 mg L-1). RESULTS: The bacterial strain showed extremely good dye-removing potential at various dye concentrations. IR studies at different temperatures showed that the dye was adsorbed on the bacterial surface at lower temperatures. Characteristics of the adsorption process were investigated by Scatchard analysis at 25°C and 35°C. Scatchard analysis of the equilibrium binding data for the dye on this bacterium gave rise to linear plots, indicating that the Langmuir model could be applied. The regression coefficients obtained for the dye from the Freundlich and Langmuir models were significant and divergence from the Scatchard plot was observed. CONCLUSION: The adsorption behavior of the dye on this bacterium was expressed by the Langmuir, Freundlich, and Temkin isotherms. The adsorption data with respect to various temperatures provided an excellent fit to the Freundlich isotherm. However, when the Langmuir and Temkin isotherm models were applied to these data, a good fit was only obtained for the dye at lower temperatures, thus indicating that the biosorption ability of R. palustris 51ATA is dependent on temperature, pH, and dye concentration.

Isolation and Identification of Orange M2R and Green GS Dye Decolourizing Bacteria from Textile Sludge (Soil) Samples and Determination of Their Optimum Decolourization Conditions

Objectives: Azo dye accounts for majorly produced synthetic dye substances in industries, posing a threat to all possible life forms. This study was focused to isolate azo dye “Orange M2R” and “Green GS” degrading bacterial strain from textile effluent soil samples and optimization of their optimum physio-chemical growth conditions. Methodology: To achieve above-mentioned objective, sludge samples were collected from textile industrial area and were applied to 1%, 3% and 5% dye containing SM broth to observe the dye degrading capability of those samples that contain acclimatized bacteria. ABIS microbiology software (Advanced Bacterial Identification Software) was used to justify and determine the identity of these bacteria with the aid of results obtained from the biochemical tests that were undertaken. Results: Bacterial strains identified in this study were Enterococcus termitis, Enterococcus camelliae, Bacillus farraginis, Bacillus muralis, Paenibacillus macerans, Bacillus decolorationis, and Macrococcus brunensis. Out of these isolates Enterococcus termitis, Bacillus farraginis, Paenibacillus macerans, Bacillus decolorationis emerged out to be most potent decolourizer, being selected for further studies. Bacillus farraginis was identified as the best decolourizer of OM2R (Orange M2R) dye that decolourized 98% of the dye and Paenibacillus macerans showed maximum decolourization on GGS(Green GS) dye that decolourized 97% of the dye. The effect of pH, NaCl, temperature and initial concentration of dye was studied with an aim to determine the optimal conditions required for maximum decolourization. The research showed different decolourization rate with varying parameters. The optimum pH for decolourization of OM2R and GGS dye was 7.0, the optimum NaCl concentration for decolourization was 2%, initial dye concentration was 1% and the temperature was 37°C for optimum decolourization by the selected isolates. Conclusion: The findings are well acclimatized and have potentials for bioremediation in textile waste effluent treatment plants.

Laccase Activity and Azo Dye Decolorization Potential of Podoscypha elegans

Azo dyes containing effluents from different industries pose threats to the environment. Though there are physico-chemical methods to treat such effluents, bioremediation is considered to be the best eco-compatible technique. In this communication, we discuss the decolorization potentiality of five azo dyes by Podoscypha elegans (G. Mey.) Pat., a macro-fungus, found growing on the leaf-litter layer of Bethuadahari Wildlife Sanctuary in West Bengal, India. The fungus exhibited high laccase and very low manganese peroxidase activities under different culture conditions. Decolorization of five high-molecular weight azo dyes, viz., Orange G, Congo Red, Direct Blue 15, Rose Bengal and Direct Yellow 27 by the fungus was found to be positive in all cases. Maximum and minimum mean decolorization percentages were recorded in Rose Bengal (70.41%) and Direct Blue 15 (24.8%), respectively. This is the first record of lignolytic study and dye decolorization by P. elegans.

Investigation of Some Parameters Affecting Methyl OrangeRemoval by Fusarium acuminatum

ABSTRACT Dye stuff released to the ecosystem from textile industries cause a serious contamination and become a major environmental problem over the last few decades. As biological decolorization of textile wastewater is an important issue, Fusarium . acuminatum was used to removal of a frequently used textile dye, methyl orange. Live pellet of Fusarium acuminatum was used and decolorization studies performed in various temperatures and pH conditions with different dye concentrations. The highest decolorization rate was observed at 35ᴼC. 60 mg/L was found as the optimum initial dye concentration. In the pH range of 3-4, decolorization rate was approximately 70%. It was seen that Fusarium acuminatum have the great ability of the methyl orange removal. To our knowledge, it took place for the first time in the literature.

Decolorization of azo dyes (Direct Blue 151 and Direct Red 31) by moderately alkaliphilic bacterial consortium

Abstract Removal of synthetic dyes is one of the main challenges before releasing the wastes discharged by textile industries. Biodegradation of azo dyes by alkaliphilic bacterial consortium is one of the environmental-friendly methods used for the removal of dyes from textile effluents. Hence, this study presents isolation of a bacterial consortium from soil samples of saline environment and its use for the decolorization of azo dyes, Direct Blue 151 (DB 151) and Direct Red 31 (DR 31). The decolorization of azo dyes was studied at various concentrations (100–300 mg/L). The bacterial consortium, when subjected to an application of 200 mg/L of the dyes, decolorized DB 151 and DR 31 by 97.57% and 95.25% respectively, within 5 days. The growth of the bacterial consortium was optimized with pH, temperature, and carbon and nitrogen sources; and decolorization of azo dyes was analyzed. In this study, the decolorization efficiency of mixed dyes was improved with yeast extract and sucrose, which were used as nitrogen and carbon sources, respectively. Such an alkaliphilic bacterial consortium can be used in the removal of azo dyes from contaminated saline environment.

Produção de lacase de Pycnoporus sanguineus em meio de cultivo à base de melaço soja / Laccase production by Pycnoporus sanguineus in culture media with soybean molasses / Producción de lacasa de Pycnoporus sanguineus en medio de cultivo con melaza de soja

Lacases são polifenol oxidases que utilizam a capacidade redox de íons cobre para reduzir oxigênio a água e oxidar um substrato fenólico. A síntese e secreção de lacases de basidiomicetos dependem de vários fatores como os nutrientes presentes no meio de cultura. Visando à produção de lacase, Pycnoporus sanguineus foi cultivado em meio contendo melaço de soja como única fonte de carbono, ureia como fonte de nitrogênio suplementar em diferentes concentrações (0,6; 1,2; 2,4; 4,8 e 9,6 g/L de nitrogênio) e diferentes concentrações de CuSO4 (0, 150, 200, 250 e 300 µM). O extrato enzimático produzido nas melhores condições de cultivo foi utilizado para a descoloração dos corantes remazol azul brilhante R (antraquinona), amarelo 145, preto 5, vermelho 195 (azo) e verde malaquita (trifenilmetano). As concentrações de nitrogênio não afetaram a produção de lacase, exceto a maior concentração (9,6 g/L) que reduziu a atividade enzimática. A adição de cobre ao meio de cultivo (150 µM) aumentou a atividade de lacase em 112%. A maior atividade de lacase (~34300 U/L) promoveu a descoloração dos corantes remazol azul brilhante R (67,5%) e verde malaquita (28,3%) em 24h, sendo os corantes azo descoloridos apenas parcialmente. Concluiu-se que o melaço de soja é um resíduo agroindustrial adequado para produção de lacase de P. sanguineus com potencial para degradação de corantes.

Laccases are multicopper oxidases using the redox ability from copper ions to reduce oxygen to water, while oxidizing a phenolic substrate. Laccase synthesis and secretion in basidiomycetes depend on the conditions provided and on the nutrients present in the culture medium. Pycnoporus sanguineus was cultivated in medium containing soybean molasses as the sole carbon source, with urea as the source of supplemental nitrogen at different concentrations (0.6, 1.2, 2.4, 4.8 and 9.6 g/L nitrogen), and different CuSO4 concentrations (0, 150, 200, 250 and 300 µM). The enzymatic extract produced under the best cultivation conditions was used for the depigmentation of remazole brilliant blue R (anthraquinone), yellow 145, black 5, red 195 (azo) and malachite green (triphenylmethane). Nitrogen concentrations did not affect laccase production, except for the higher concentration (9.6 g/L) reducing enzymatic activity. The addition of copper to the culture medium (150 µM) increased laccase activity by 112%. The highest laccase activity (~34300 U/L) promoted the depigmentation of remazol brilliant blue R (67.5%) and malachite green (28.3%) dyes in 24 hours. Azo dyes were only partially discolored. Therefore, it can be considered that soybean molasses is an agro-industrial byproduct suitable for the production of P. sanguineus laccase with potential for dye degradation.

Lacasas son polifenoles oxidasas que utilizan la capacidad redox de iones de cobre para reducir el oxígeno del agua y oxidar un sustrato fenólico. La síntesis y secreción de lacasas de basidiomicetos dependen de las condiciones como los nutrientes presentes en el medio de cultura. Buscando la producción de lacasa, se cultivó Pycnoporus sanguineus en medio que contenía melaza de soja como única fuente de carbono, urea como fuente de nitrógeno suplementar a diferentes concentraciones (0,6, 1,2, 2,4, 4,8 y 9,6 g/L de nitrógeno) y diferentes concentraciones de CuSO4 (0, 150, 200, 250 y 300 µM). El extrato enzimático producido en mejores condiciones de cultivo ha sido utilizado para la decoloración de los colorantes remazol azul brillante R (antraquinona), amarillo 145, negro 5, rojo 195 (azoico) y verde malaquita (trifenilmetano). Las concentraciones de nitrógeno no afectaron la producción de lacasa, excepto la mayor concentración (9,6 g/L) que redujo la actividad enzimática. La adición de cobre al medio de cultivo (150 µM) aumentó la actividad de la lacasa en un 112%. La mayor actividad de lacasa (~34300 U/L) promovió la decoloración de los colorantes remazol azul brillante R (67,5%) y verde malaquita (28,3%) en 24h, siendo que los colorantes azoicos fueran parcialmente decolorados. Se concluye que la melaza de soja es un desecho agroindustrial adecuado para la producción de lacasa de P. sanguineus con potencial para degradación de colorantes.

Action of Ponceau 4R (E-124) food dye on root meristematic cells of Allium cepa L / Ação do corante alimentar Ponceau 4R (E-124) sobre as células meristemáticas de raízes de Allium cepa L

This study aimed to evaluate the toxicity of Ponceau 4R food dye on the cell cycle in root meristematic cells of Allium cepa L. at three concentrations: 0.25, 0.50 and 0.75 g L-1, at exposure times of 24 and 48 hours. For each concentration, we used a set of five onion bulbs that were first rooted in distilled water and then transferred to their respective concentrations. Radicles were collected and fixed in acetic acid (3:1) for 24 hours. The slides were mounted with the crushing technique and stained with 2% acetic orcein. Cells were analyzed throughout the cell cycle, totaling 5,000 cells for each control and exposure time. The calculated mitotic indices were subjected to the Chi-square test (p < 0.05). From the results, we observed that the concentrations of 0.25 and 0.50 g L-1 at the 48-hour exposure, and the concentration of 0.75 g L-1, the two exposure times time significantly reduced (p < 0.05) the cell division rate. Importantly, all the three concentrations at the two exposure times tested caused cellular aberrations in significant numbers in this testing system. Therefore, under the conditions studied, the Ponceau 4R was cytotoxic.

Este trabalho teve por objetivo avaliar a toxicidade do corante alimentar Ponceau 4R sobre as células meristemáticas de raízes de Allium cepa L., em três concentrações: 0,25; 0,50 e 0,75 g L-1, nos tempos de exposição de 24 e 48 horas. Para cada concentração utilizou-se um grupo de cinco bulbos de cebolas, que primeiramente foram enraizados em água destilada, e em seguida transferidos para as suas respectivas concentrações. As radículas foram coletadas e fixadas em ácido acético (3:1) por 24 horas. As lâminas foram preparadas pela técnica de esmagamento e coradas com orceína acética a 2%. Analisaram-se células em todo ciclo celular, totalizando 5.000 para cada controle e tempo de exposição. Os índices mitóticos calculados e as aberrações celulares observadas foram submetidos à análise estatística do Qui- quadrado (p < 0,05). A partir dos resultados observou-se que as concentrações 0,25 e 0,50 g L-1, no tempo de exposição de 48h, e a concentração 0,75 g L-1, nos dois tempos de exposição avaliados reduziram de forma significativa (p < 0,05) o índice de divisão celular do sistema teste em questão. Observou-se também que todas as três concentrações, nos dois tempos de exposição analisados, ocasionaram aberrações celulares em número significativo a este sistema teste. Portanto, nas condições analisadas, o Ponceau 4R foi citotóxico.

Microbial dynamics during azo dye degradation in a UASB reactor supplied with yeast extract

The present work aimed to investigate the microbial dynamics during the anaerobic treatment of the azo dye blue HRFL in bench scale upflow anaerobic sludge bed (UASB) reactor operated at ambient temperature. Sludge samples were collected under distinct operational phases, when the reactor were stable (low variation of color removal), to assess the effect of glucose and yeast extract as source of carbon and redox mediators, respectively. Reactors performance was evaluated based on COD (chemical oxygen demand) and color removal. The microbial dynamics were investigated by PCR-DGGE (Polimerase Chain Reaction - Denaturing Gradient of Gel Electrophoresis) technique by comparing the 16S rDNA profiles among samples. The results suggest that the composition of microorganisms changed from the beginning to the end of the reactor operation, probably in response to the presence of azo dye and/or its degradation byproducts. Despite the highest efficiency of color removal was observed in the presence of 500 mg/L of yeast extract (up to 93%), there were no differences regarding the microbial profiles that could indicate a microbial selection by the yeast extract addition. On the other hand Methosarcina barkeri was detected only in the end of operation when the best efficiencies on color removal occurred. Nevertheless the biomass selection observed in the last stages of UASB operation is probably a result of the washout of the sludge in response of accumulation of aromatic amines which led to tolerant and very active biomass that contributed to high efficiencies on color removal.

Effect of antioxidant vitamins A, C, E and their analogues on azo-dye binding protein in liver of rats treated with p-dimethylaminoazobenzene.

p-Dimethylaminoazobenzene (DAB) is an azo-dye and known to cause liver tumour in rats. Azo-dye binding protein is a specific cytosolic protein involved in the translocation of azo-dye carcinogen metabolites from liver cytoplasm into the nucleus. Administration of vitamin A (40,000 and 50,000 IU), L-ascorbic acid (500 and 1,000 mg) and vitamin E succinate (200–500 mg) reduced the amount of azo-dye binding protein in liver of rats treated with DAB. Supplementation of high doses of vitamin A acetate, vitamin A palmitate, sodium ascorbate, ascorbyl palmitate and vitamin E acetate had no effect on the quantity of azo-dye binding protein in liver. When the vitamin mixture was given, the level of azo-dye binding protein decreased in the liver at all the studied doses, which may be due to their synergistic effect.

Descoloração redutiva do corante azo RR2 na ausência e presença de mediador redox e aceptor de elétrons nitrato / Reductive decolorization of the azo dye RR2 in the absence and presence of redox mediator and the electrons acceptor nitrate

A presente investigação teve como objetivo estudar o efeito do nitrato na descoloração de corantes em reatores anaeróbios suplementados ou não com mediadores redox. Dois reatores anaeróbios em paralelo foram operados com tempo de detenção hidráulica (TDH) de dez horas, utilizando-se etanol como cossubstrato. Os resultados provaram que os reatores eram eficientes na remoção de cor, sendo o composto etanol um eficiente doador de elétrons para sustentar a redução do corante azo nos reatores mesofílicos. O mediador redox AQDS aumentou as taxas de redução do corante azo, mas o seu efeito não foi tão marcante comparado aos experimentos realizados anteriormente. Contrariamente às hipóteses levantadas de que a adição de nitrato poderia interferir nas taxas de remoção de cor e propriedades catalíticas do mediador redox, não se verificou nenhum efeito desse composto.

This paper aimed at evaluating the effect of nitrate on anaerobic azo dye reduction by using mesophilic bioreactors, in the absence and in the presence of redox mediators. Two anaerobic bioreactors were operated in parallel with a hydraulic retention time (HRT) of ten hours; ethanol was used as co-substrate. The results showed that the bioreactors were efficient on dye reduction, and the ethanol showed to be a good electron donor to sustain it. The redox mediator AQDS increased the rates of reductive decolourisation, but its effect was not so remarkable compared to the previous experiments conducted. Contrary to the raised hypothesis that nitrate addition could decrease the colour removal efficiency and catalytic properties of the redox mediators, no effect of nitrate was observed in the bioreactors.

Avaliação da degradação do corante vermelho bordeaux através de processo fotoquímico / Assessment of red dye degradation through photochemical process

Neste trabalho foi realizado o estudo da degradação fotoquímica do corante vermelho bordeaux. O estudo objetivou a avaliação de tratamentos alternativos com vistas à aplicação de tecnologias limpas. Os experimentos de fotodegradação foram realizados através da incidência de radiação UV em um compartimento contendo o corante (solução). O tratamento fotoquímico reduziu em 99 por cento a coloração e a concentração da solução contendo o corante vermelho bordeaux.

This paper studied the photochemical degradation of food dye (red dye). The investigation aimed at the assessment of alternative treatments, focusing the use of clean technologies. The photochemical degradation experiments were performed in a compartment with UV radiation (mercury lamp - 250W). The photochemical treatment showed a 99 percent color and concentration reduction in the dye solution.

The Decolorizing Characterization of Shewanella decolorationis S12~T / 微生物学通报

High efficient dyes decolorizing bacterium, strain S12~T, was isolated from activated-sludge of textile-printing wastewater treatment plant. The strain was identified as a novel specie of the genus Shewanella, for which the name Shewanella decolorationis sp. nov. is proposed. It's decolorizing rate reached 96% in 4h, when 50mg/L of azo dye was used. The organism exhibited a remarkable color removal capability, even at azo dye's concentration of 2,000mg/L. A clear decolorizing zone around each colonies appeared after four days grown on LB plate containing 500mg/L azo dye. The changes of UV-visible spectra of azo dye solution indicate that the color removal was largely attributed to biodegradation. The decolorizing enzymes of strain S12~T were constitute type and not secreted to the culture medium.

Isolation and Characteristic of an Azo Dye-decolorizing Salt-tolerant Bacteria Strain GYW / 微生物学通报

A salt-tolerant strain GYW capable of decolorating azo dye was isolated and identified as Halo-monas sp.by 16S rDNA.The result showed that the decolorizing salt-tolerant bacteria could survive above the 10% salt concentration and it could decolorize many dyes.The strain had a high decolorizing rate on acid red GR under the condition of pH 7.5,anaerobic 30?C and 10% NaCl.The ion of Cl- strong inhibited the decolorization of acid red GR,and the ion of SO42- affected little on the decolorization,and the lycine addi-tion with the optimal concentration of 200 mg/L could enhanced the decolorization rate under high NaCl concentration.